Before providing the engine with new gasoline I checked in the tank. I spotted some rust inside the tank, which won't provide reliable fuel supply if the rust blocks the fuel line.
The tank is an aftermarket replacement made by Tankauto. The metal seems a bit on the thin side. Any more serious rust and there is not much buffer before the tank rusts through. Luckily, this tank is not so bad. I think I caught it just in time. There is a small pinhole leak on the underside that should fill in with the sealant.
I also wanted to check the condition of the tank and of the floor under the tank. There was a lot of surface rust on the underside of the tank. The carpet used to isolate the tank from the chassis was also damp, moldy, and crumbling.
The floor is ordinary sheet, clearly a replacement for the original. It, too, was badly rotted at the rear and with surface rust.
I'll be using the KBS Coatings Tank Seal kit on this. I've used KBS products on a bunch of other products and the finished result is usually fantastic.